The temporomandibular disorders (TMDs) are a group of conditions involving masticatory muscles and/or temporomandibular joints and characterized by chronic facial pain. It has long been recognized that the etiology and pathogenesis of TMDs are multifactorial, including a strong association with the occurrence of environmental stressors and stress-related psychiatric disorders such as depression and post-traumatic stress disorder (PTSD). A striking feature of TMDs is the strong predominance of women with these disorders (75-84%). Any hypothesis of the pathogenesis of TMDs will need to explain: a) why TMDs are so much more common in women and b) the underlying relationship of TMDs with stress and depression. It now appears that dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, the main stress hormone axis, can provide an explanation for these associations in TMDs. In this study, we will examine the hormones of the stress axis, ACTH and cortisol over a 24 hour period. Blood will be drawn through an intravenous catheter every 10 minutes for 24 hours in women with TMD and normal women without TMD.